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Chat => Sports, Hobbies & Motors => Topic started by: maximusotter on March 31, 2006, 16:06:13 PM

Title: 6 stroke engine
Post by: maximusotter on March 31, 2006, 16:06:13 PM
Props to Skidzilla for turning us on to the site.

http://www.damninteresting.com/?p=467#more-467

Very simple concept, at the end of the normal exhaust stroke, a tiny bit of water is injected into the already hot cylinder, where it immediately expands, creating another power stroke from the heat that is otherwise wasted.

:thumbup:

On another note, the external combustion engine:
http://uncyclopedia.org/wiki/External_combustion_engine
Title: Re:6 stroke engine
Post by: madmax on March 31, 2006, 16:37:23 PM
gonna be intresting if that ever takes off,
only problem i can see is making the two tank inlets different enough to make  half asleep people not fill up the petrol tank with water and vice versa.

that and stainless steel exhausts would probably have to become the norm...

steam = water, water + normal steel = rust
Title: 6 stroke engine
Post by: maximusotter on March 31, 2006, 16:44:16 PM
You should be able to collect water from the exhaust, where it is steam distilled, steam comes out regular exhaust as well.

Biggest problem is oil contamination, tbh, but the amount of water needed to provide power would be very small. Just keep your rings in good condition. :P
Title: 6 stroke engine
Post by: Chris on March 31, 2006, 17:48:05 PM
but water is stupidly dense, at 1kg per litre... its heavy stuff!

And it will freeze, meaning that additives are necessary, which might leave deposits...  Still needs a lot of work before it will be commercially viable, methinks.
Title: Re:6 stroke engine
Post by: Pete on March 31, 2006, 17:52:38 PM
Cooler engine = richer mixture required, still its a nice bit of engineering :)

Cool website too  :thumbup:
Title: 6 stroke engine
Post by: Serious on March 31, 2006, 18:18:26 PM
Quote from: Chris
but water is stupidly dense, at 1kg per litre... its heavy stuff!

And it will freeze, meaning that additives are necessary, which might leave deposits...  Still needs a lot of work before it will be commercially viable, methinks.


Water may have a greater mass but you save almost as much fuel so for a driver who wants economy it may be preferential. As for additives providing you choose the right ones it should be OK but I suspect a lot of work will have to be done on this, same with deciding on the materials for the engine.
Title: Re:6 stroke engine
Post by: Chris on March 31, 2006, 20:40:27 PM
Quote from: sdp
Cooler engine = richer mixture required, still its a nice bit of engineering :)

Cool website too  :thumbup:


it could be possible to only run the "6 stroke" cycle when it is running hot, perhaps while idling in traffic etc... and as the article says it reduces  (if not eliminates) the need for water cooling in the block and head.
Title: 6 stroke engine
Post by: knighty on March 31, 2006, 22:15:10 PM
that link says bit 18 wheeler lorries have radiators that weigh 1000lb..... wtf?

454kg ? almost half a tonne ?

BS ! :p
Title: Re:6 stroke engine
Post by: Serious on March 31, 2006, 23:32:58 PM
Quote from: sdp
Cooler engine = richer mixture required,


Does it?

Quote from: Chris
Quote from: sdp
Cooler engine = richer mixture required, still its a nice bit of engineering :)

Cool website too  :thumbup:


it could be possible to only run the "6 stroke" cycle when it is running hot, perhaps while idling in traffic etc... and as the article says it reduces  (if not eliminates) the need for water cooling in the block and head.


Its quite possible to run car engines without any water cooling at all if you use an air cooled design like in the Volkswagen Kubelwagen or 2CV, works even in the desert.
Title: 6 stroke engine
Post by: maximusotter on March 31, 2006, 23:42:09 PM
Thats not the point, the point is redirecting otherwise lost energy into engine power.
Title: 6 stroke engine
Post by: Christopher Monkey on April 01, 2006, 00:12:51 AM
Very very good idea, but why not make it a hemi and have three valves per cylinder:

1- inlet
2- gas exhaust
3- water exhaust

then use the redundant water pump to flow the water back into the tank, therefore reducing the number of fill-ups of water?
Title: Re:6 stroke engine
Post by: madmax on April 01, 2006, 01:46:19 AM
problem is with the heat you have to extract from the steam before you can shove it back into the cylender.


water evaporates and takes in heat, to recondese it lets out heat....
so you end up running a radiator and fan arrangement on the recirculated water..... maybe something more elaborate even.

square one anyone?  :lol:




with the 6 stroke setup, woulda thought youd have to run a few fully fuel cycles before it warms up enough to start hitting the water cycles.


oh the colder engine = richer mixture, i dont think is quite right.
colder air = denser air = more oxygen in the cylender for combustion.
Title: Re:6 stroke engine
Post by: Serious on April 01, 2006, 02:13:41 AM
Quote from: madmax
problem is with the heat you have to extract from the steam before you can shove it back into the cylender.


water evaporates and takes in heat, to recondese it lets out heat....
so you end up running a radiator and fan arrangement on the recirculated water..... maybe something more elaborate even.

square one anyone?  :lol:



Not quite, steam engines usually have a condenser to turn the steam back into water in order to reuse it. OK you would need additional parts to do that but its not going to be that difficult. The condensed water will still be near boiling so you could put more of it into the cylinder too resulting in even greater efficiency.

It would also reduces the need for a stainless steel exhaust.
Title: 6 stroke engine
Post by: Christopher Monkey on April 01, 2006, 03:48:16 AM
Exactly what i was thinking, just didnt want to sound like a steam freak! :d
Title: Re:6 stroke engine
Post by: M3ta7h3ad on April 01, 2006, 04:15:59 AM
The post someone made as a comment covers 2 important issues.

1.) Oil emulsification, as piston seals are never 100%.

2.) It could infact be harming the fuel efficiency of the engine, An engine uses the residual heat to help ignite the fuel thats injected, by getting rid of that heat.. you could infact be lowering fuel efficency of an engine, purely to get it back in the last cycle.

:|
Title: Re:6 stroke engine
Post by: Chris on April 01, 2006, 10:57:11 AM
Quote from: M3ta7h3ad
The post someone made as a comment covers 2 important issues.

1.) Oil emulsification, as piston seals are never 100%.

2.) It could infact be harming the fuel efficiency of the engine, An engine uses the residual heat to help ignite the fuel thats injected, by getting rid of that heat.. you could infact be lowering fuel efficency of an engine, purely to get it back in the last cycle.

:|


I wouldnt be concerned with the efficiency being lowered too much, as the water injection would partially - if not wholly - replace the conventional water cooling setup of the engine.  it can be set up to only come on once the engine is up to temperature, and if the water entering the cylinder is as hot as the regular coolant, then it should have a comparable effect on cooling.

this means the cooling would still take place, but instead of venting this heat to atmosphere via a radiator, it converts it into power via expansion.
Title: Re:6 stroke engine
Post by: dogbert on April 01, 2006, 11:41:04 AM
Its a STEAM ENGINE.

You only need HEAT to make STEAM. So Petrol as a heat source is only one solution....yes, we have a half-way house here using the excess HEAT from a COMBUSTION engine.

But...think about the future possbilites....instead of going back to using solid fuel (coal / wood ) to heat a boiler to make steam and drive the pistons. You could use another heat source....NUCLEAR.

NUCLEAR fuel (metal rods) produce HEAT...the heat output is controled by mass, the more mass the greater the heat output...so in a NUCLEAR power station the metal rods are moved closer and further appart to control the mass.

Water is then added which turns to steam and powers electric turbines.

The same principle could be used in a CAR engine. Simply, using a pair of NUCLEAR fuel rods and a tank of water. Starter motor cranks the engine and pumps in the water, nuclear rods are at full contact and producing heat...water vaprosises into steam off we go.

And heres how you do it! Make the internal Pistons and Cyclinger out of Plutonium. As the engine rotates, the piston rises in the cyclinder, thuss moving the nuclear fuel closer together, mass increases, heat produced, water added, steam forces piston down in power stroke...etc and we have a NUCLEAR POWERED CAR ENGINE !!
Title: Re:6 stroke engine
Post by: brummie on April 01, 2006, 11:48:37 AM
lol some how i can think of loads of reasons why that is not going to happen
Title: Re:6 stroke engine
Post by: Chris on April 01, 2006, 12:05:10 PM
Quote from: dogbert
Its a STEAM ENGINE.

You only need HEAT to make STEAM. So Petrol as a heat source is only one solution....yes, we have a half-way house here using the excess HEAT from a COMBUSTION engine.

But...think about the future possbilites....instead of going back to using solid fuel (coal / wood ) to heat a boiler to make steam and drive the pistons. You could use another heat source....NUCLEAR.

NUCLEAR fuel (metal rods) produce HEAT...the heat output is controled by mass, the more mass the greater the heat output...so in a NUCLEAR power station the metal rods are moved closer and further appart to control the mass.

Water is then added which turns to steam and powers electric turbines.

The same principle could be used in a CAR engine. Simply, using a pair of NUCLEAR fuel rods and a tank of water. Starter motor cranks the engine and pumps in the water, nuclear rods are at full contact and producing heat...water vaprosises into steam off we go.

And heres how you do it! Make the internal Pistons and Cyclinger out of Plutonium. As the engine rotates, the piston rises in the cyclinder, thuss moving the nuclear fuel closer together, mass increases, heat produced, water added, steam forces piston down in power stroke...etc and we have a NUCLEAR POWERED CAR ENGINE !!


Crash the car, radioactive material EVERYWHERE.

itll never work.
Title: Re:6 stroke engine
Post by: M3ta7h3ad on April 01, 2006, 12:35:14 PM
april fools?? :| lol
Title: 6 stroke engine
Post by: bear on April 01, 2006, 17:35:41 PM
I think there is water injection systems for 4-strokes to lower fuel consumption.
Title: Re:6 stroke engine
Post by: bear on April 01, 2006, 17:40:49 PM
Quote from: M3ta7h3ad
april fools?? :| lol


Article is from the 18th of march
Title: 6 stroke engine
Post by: bear on April 01, 2006, 17:48:28 PM
http://www.hotrodders.com/forum/100-miles-per-gallon-13319-5.html